Drop bottom door latching equipment for mine cars



Dec. 5, 1944. H. w. SANFORD 2,364,554

DROE BO/'ITOM DOOR LATCHING EQUIPMENT FOR MINE CARS Dec. 5, 1944. H.1 w. sANFoRD 2,364,554

DROP BOTTOM DOOR LATCHING EQUIPMENT FOR MINE CARS Filed Feb. 26, 1941 6 Sheets-Sheet 2 fw Q 'x @SWS w Dec. 5, 1944. H. w. SANFORD DROP BOTTOM DOOR LATCHING EQUIPMENT FOR MINE CARS e sheetssheet s Filed Feb. 26, 1941 Zh/usara@ Dec. 5, 1944. H, W SANFORD 2,364,554

DROP BOTTOM DOOR LATCHING EQUIPMENT FOR MINE CARS Filed Feb. 26. 1941 6 Sheets-Sheet 4 Mar Dec. 5, 1944. H, W SANFORD 2,364,554

DROP BOTTOM DOOR LATCHING EQUIPMENT FOR MINE CARS Filed Feb. 26, 1941 6 Sheets-Sheet 5 Dec. 5, 1944. H w, SANFORD 2,364,554

DROP BOTTOM DOOR LATCHING EQUIPMENT FOR MINE CARS Filed Feb. 26, 1941 6 Sheets-Sheet 6 Zh/VEN raf? 577-0 @fmif@ Patented Dec. 5, 1944 DROP BOTTOM DOOR LATCHING EQUIPMENT FOR MINE CARS Hugh W. Sanford, Knoxville, Tenn.

Application February 26, 1941, Serial No. 380,718

(Cl. S-286) 24 Claims.

The invention relates generally to mine cars wherein the lading is supported on one or more drop bottom doors, and it primarily seeks to provide novel latching equipment for normally securing the door or doors in lading supporting position and releasable for allowing said door or doors to drop and discharge the supported lading at a predetermined point along the trackways over which the mine cars travel.

Drop bottom mine cars are well known and examples thereof are disclosed 1,268,344 and 1,889,066 issued to Charles A. Grifiith on June 4, 1918, and November 29, 1932, respectively. Such cars have body structure of conventional form and usually include a bottom opening through which lading is `to be dumped and normally closed by a plurality of downwardly swingabl lading supporting and discharging doors. Each such door has its foremost portion hinged transversely of the length of the car, and the doors are so cooperatively arranged that the free or rearmost edge of each door `but the rearmost is releasably supported by the next succeeding door,l said rearmost door being releasably supported by a latch mechanism usually tripped by engagement with a roadside ramp. Releasing of this latching equipment permits therearmost door to drop and discharge the overlying lading, and the remaining doors are successively and automatically released. The automatic releasing of doors, Aand the automatic return to normal and relatching of said doors are described in detail in prior patents such as the Griffth patents hereinbeiore referred to. lAs will be obvious by reference to these and similar patents, previously known latching equipments have necessarily projected transversely beyond the lateral limits of the car structures and have been often damaged by contact with roadside obstructions. Obviously, this is objectionable, and the present invention seeks to provide a novel drop bottom door latching equipment which will avoid the difficulties mentioned and provide other safety features.

Therefore, it is an object of the present invention to provide a novel drop bottom door latching equipment for mine cars and means for releasing the same at the appointed time so constructed and arranged that no part of the latching equipment will project laterally beyond the mine car body connes during normal travel thereof when roadside obstructions are likely to be encountered.

Another object of the invention is to provide novel means for tripping the latching equipment.

in patents,`

Another' object of the invention is to provide novel electrically actuatedmeans for controlling the automatic tripping of the latching equipment, said means being effective during forward movement only of the mine cars.

Another object of the invention is to provide a latching equipment of the character stated including means for locking the equipment against inadvertent release.

Another object of the invention is to provide a latching equipment of the character stated including a latch lever having a portion normally retracted within the lateral confines of the mine car but movable beyond the car side for tripping engagement with a roadside ramp.

Another object of the invention is to provide a latching equipment of the character stated in which is included means for automatically locking the latch lever in the latching position whenever the retractible portion thereof is retracted.

Another object of the inventionis to provide a latching equipment of the character stated including means `for manually or mechanically moving the retractible lever portion between projected and retracted positions.

With the above and other 'objects in view that will hereinafter appear, the nature of the invention will be more fully understood by following the detailed description, the appended claims and the several views illustrated in the accompanying drawings.

In the drawings:

Figure 1 is a somewhat diagrammatic side elevation illustrating the invention.

Figure 2 is a somewhat diagrammatic plan View of the parts shownin Figure 1, the mine car being omitted.

Figure 3 is a somewhat diagrammatic vertical ing the parts positioned as in Figure 5.-

plan view of the latch portion depressing cam shown in Figure 8.

Figures ll and 12 are enlarged detail views illustrating the solenoid controlling contact maker in side and end view respectively.

Figure 13 is an enlargedl fragmentary rear elevation of a mine car equipped with a modified form of latch mechanism.

Figure 14 is a fragmentary right side 'elevation of the parts shown in Figure 13.

In the accompanying drawings, in which an example of embodiment of the invention is illustrated, the usual dump pit or storage bin into which lading is dumped from moving-mine cars is indicated at 5. The rails over which the cars travel are indicated at 6, and the mine cars, generally designated 1, travel over these rails on the usual wheels 8 and include any conventional form of body structure 9 and end bumpers I0. The dump opening through the bottom of each car is closed by drop bottom doors I I, each transversely pivoted at its leading edge, as at I2, and having its rearmost' or free edge supported by the pivoted edge portion of the next succeeding door, the rearmost door being equipped with the usual latch lug I3 which is releasably secured by the latch I4. The latch is pivotally mounted, as at I5, at the rear of the car and includes a cam nose portion I6.

The usual door lifting cams are indicated at I1, and the door closing ramp is indicated at I8. See Figures l. and 2 of the drawings.

The usual trolley wire isindicated at I9 and may be connected, as at 2i), with a suitable power source. This trolley wire may be supported beside the trackway in the mannerl best illustrated in Figure 3 of the drawings, and the usual latch tripping ramp 2| is also mounted beside the trackway in proper relation to the pit or storage bin as best illustrated in Figures l and 3 of the drawings.

All of the parts hereinbefore described may be conventional in form, and in themselves form no part of the present invention.

The present invention involves the provision of novel latching equipment in combination with the parts hereinbefore described, and in adapting these novel equipments to practical use, as

illustrated in the accompanying drawings, a

solenoid controlling contact maker, generally designated 22, and a latch portion depressing cam, generally designated 23, are provided and positioned in the manner somewhat diagrammatically illustrated in Figures 1, 2 and 3 of the drawings. The purposes of these parts will be described in detail as this description progresses.

In the practical development of the improved latching equipment, there is provided a latch lever 24 which is secured to the latch member for the purpose of imparting movement thereto in the manner illustrated in Figures 4; and 5 of the drawings. It will be observed by reference to the figures mentioned that this lever is in the nature of a flat bar which terminates short of projection beyond the side of the car body structure.

A lever extension piece 25 is pivoted, as at 26, to the free end of the lever 24, and this piece is composed of two like plates 21 opposed in parallel spaced relation, said plates being held apart by spacer sleeves 28 in a manner for avoiding frictional contact with the front and rear faces of the lever 24. One such spacer sleeve surrounds a stop pin 29 which limits upward swing- LEU ' means.

ing movement, or movement of extension, of the piece 25.

The plates 21 are equipped with aligned lock notches 3U engageable with a lock lug 3I welded or otherwise secured to the rear end of the mine car, and the rearmost plate carries an anchor e'ar 32 which serves as an anchor for one end of a retainer spring equipment 33, the other end of this equipment being adjustably anchored, as at 34, to a lug 35 fixed to the rear of the car structure. The ear 32 is so placed with relation to the extension piece pivot 25 that the spring equipment will be effective to yieldably hold the extension piece 25 in its elevated or extended position illustrated in Figure 5, or in its lowered or retracted, normal position illustrated in Figure 4.

It will be obvious that when the plate notches 30 are engaged with thelock lug 3|, the last lever 24 cannot be lifted, and by reason of the provision of this equipment, inadvertent releasing of the latch I4 is impossible. It will also be observed by referenceto Figure 4 of the drawings that the edge portions 36 of the plates 21 are shaped to conform generally to the side contour of the mine car, thereby to avoid projection of any part of the latch equipment beyond the side limits of the mine car during travel thereof.

The connected plates 21 carry a handle pro- .jection 31 which can be grasped with facility to move the extension piece 25 from the retracted position illustrated in Figure 4 to the projected position illustrated in Figure 5, or vice versa.

During normal travel of the mine cars the extension piece 25 is retained by the spring equipment 33 in the retracted and safely locked position illustrated in Figure 4. It is to be understood that the extension piece is shifted from the retracted position illustrated in Figure 4 to the extended position illustra-ted in Figure 5 at some time prior to the intended dumping of the cars. 'I'his can be accomplished manually, by manipulation of the handle 31, or mechanically, in a manner later to be described, and when the extension piece is projected in the manner illustrated in Figure 5, it is in position for riding over and engaging the latch tripping ramp hereinbefore referred to and generally designated 2I. This ramp includes an upwardly and forwardly inclined latch lever lifting rail 38 which is suitably supported on standards 39 beside the trackway in the manner illustrated in Figures l, 2 and 3 of the drawings. It will be obvious that when the extension piece 25 rides over this rail, the latch lever 24 will be lifted and the latch I4 swung about its pivotal mounting and released so as to release the latch lug I3 and permit the drop bottom doors to swing downwardly and discharge the lading supported thereby into the dump pit or bin 5.

As previously stated, the extension piece 25 can be moved from its safety position illustrated in Figure 4 to its effective, latch lever tripping position illustrated in Figure 5 by mechanical For this purpose, the plates 21 are equipped with an abutment piece 4D engageable by the reciprocable core 4I of a solenoid 42 fixedly mounted at the rear of the car structure in the path of movement 0f the extension piece. The solenoid is grounded to the car structure, as at 4,3, and is connected by an insulated wire 44 with a contact member 45 secured to and insulated from the car side and disposed in position for engaging with the contact maker 22 mounted at the and latched. 'While the'latchin'g Yof the doors is' side `of the trackway in the manner illustrated in Figures 1, 2 and 3 of the drawings.

It will be observed -by reference to Figures 1 and 2 of the drawings that the contact maker 22` is disposed slightly in advance of the latch tripping ramp 2|, and each time the contact member 45 on a given car engages the contact member 22, the solenoid 42 on that particular car is energized and its core is projected against the adjacent abutment piece 4|) and serves to mechanically swing the particular extension piece 25 from its retracted, safety position illustrated in Figure 5. This projectionof the extension piece will be effected in time to permit the extension piece to engage vthe latch tripping ramp rail 38 for effecting a latch releasing operation. in the manner hereinbefore described.v

The contactmaker 22 is preferably constructed in the manner illustrated in Figures 11 and 12 of the drawings, and is connected by an insulated wire 46 with the trolley lwire i9 in `the manner diagrammatically illustrated in Figure 3 of the drawings. The contact maker preferably includes a standard 41 pivoted near its lower end, as at 48, on a support boxing 49 into which the lower extremity of the standard extends, and it is yieldably helderect by a retractile spring equipment 50. At its upper end the standard carries an upwardly and forwardly inclined contact plate disposed in the path of travel of and adapted to be contacted by the contact members 45 fixed to the sides of the mine cars. The contact plate 5| merges with a downwardly and forwardly inclined insulating piece 52, and it will be observed ,by reference to Figure 11 yof the drawings, that the insulating `piece includes a crown extension 53. When mine cars are traveling forwardly, the contact members 45 thereof can properly engage the contact plate 5|' for `completing the electrical circuit necessary for energizing the solenoid and properly positioning the latch leve'r extension piece, but when the mine cars are moving rearwardly the Contact members 45 carried thereby engage the insulating p-iece 52 and this insulating piece and its crown extension 53 assure against electrical contact between the moving contact members 45 and the contact plate 5|, and inadvertent latch piece projection and dump bottom door dropping are thus rendered impossible.

The latch lever extension piece depressing cam hereinbefore referred to and generally designated 23, includes a downwardly, forwardly and inwardly inclined rail 54 mounted on supporting standards 55 in position for engaging the mine accomplished just prior to depressionv of this lextension piece, it will be obvious that the depression of the extension pieceserves as an 'additional means 'of assuring proper latching of the doors. It will be'obvious from the foregoingdescription that 'the projection and retraction of ythe latch lever extension piece can be effected mechanical1y, through the medium of the solenoid 42 and the. cam 23, or manually through use of the handle member 31,

car carried extension pieces 25 in the manner best illustrated in Figure 8 of the drawings. See also Figures 1, 2, 9 and 10. The standards are hingedly mounted, as at 56, on a supporting base 51, and a spring equipment 58, anchored as'at 59 to the base 51 and as at 60 on one standard, serves to hold the standards `in the erect podropbottom doors have been completely closed I In Figures 13 and 14 a modified form of latch equipment is illustrated. In this form of the invention the latch 62 is` 4secured to a latch lever 63 which is pivoted intermediate its ends, as at 64, on the rear of the car structure. It will be observed by reference to Figure 13 that the lever is so pivoted as to provide long and short end portions,` and that the long end terminates short of projection beyond the side ofthe car so as to avoid damaging contact thereof with any roadside obstructions. This long end of the lever is equipped with a handle portion 65 so that the Asame can be manipulated manually if desired.

The shorter end 66 of the lever is urged upwardly, or to the latching position, by a compression spring equipment 61 in the manner illustrated in Figure 13.

,An abutment piece 68 is carried by the longer end of the lever, and is engaged by the reciprocable core 69 of a solenoid 1.0 which is rigidly secured to the ,rear of the car structure by the said lever. The solenoid is grounded to the car structure, as at 1|, and is connected by an insulated wire 12 with a contact member 13 secured to and insulated from the side of the car. The contact maker 13 is engageable with a contact member 14 mounted at the side ofthe trackway. As in the other form of the invention previously described, the rails 6 are bonded and are connected with a generator 15, or other suitable power source likewise connected with the trolley wire with which the contact member 14 is connected. Thus it will be obvious that each time the contact maker 13, carried at the side of a given mine car, engages the contact member 14, a circuit will be completed through the rails, the generator, the trolley wire, the wire 12, and the car structure thereby energizing the solenoid 10 and causing its core 96 to be projected. Projection of the core will lift the latch lever -63 and release the latch 62.

It is preferred that a manually operable switch 16 be connected in the wire by which the contact maker 22 or the contact member 14 is connected with the trolley wire I9 so that the electric current can be controlled by an operator standing beside the track. In this manner it is possible for an operator standing beside the track to prevent certain cars from discharging their load into the dump pit or storage bin. By observing cars `as they are passing, the operator can select cars and control the vcircuit so as' to dump selected cars only, or effect a dumping of all car except certain selected cars.

It has been stated herein that the latch lever extension piececan be extended manually, or mechanically by use of the solenoid 42. If it is intended that extension of the piece 25 be effected manually in general use, the solenoid can bev eliminated entirely. The hand manipulation or setting of the extension piece 25 may be used in conjunction with the solenoid equipment and actuated optionally therewith, or it may be used in an emergency, as when the electrically controlled solenoid equipment is for some reason disabled.

It is of course to be understood that the details of structure and arrangement of parts may be variously changed and modified without departing from the spirit and scope of my invention.

-1. In lading hauling and dumping equipment,

. the combination of a lading carrying vehicle wherein is provided lading supporting and dump door equipment and means including a latch for releasably securing the dump door equipment in lading supporting position, a latch lever for moving the latch to a door equipment releasing position, said lever including a portion normally retracted within the lateral dimensional limits of the vehicle and movable beyond said limits for latch tripping engagement with a tripping means, latch tripping means disposed along the path of travel of the vehicle, and automatically operable means for returning said lever portion to itsretracted position after tripping of said latch.

2. In lading hauling and dumping equipment, theV combination of a lading carrying vehicle wherein is provided lading supporting and dump door equipment and means including a latch for releasably securing the dump door equipment in lading supporting position, a latch lever for moving the latch to a door equipment releasing position, said lever including a portion normally retracted within the lateral dimensional limits of the vehicle and movable beyond said limits for latch tripping engagement with a tripping means,

automatically operable means for moving said lever portion to its extended position, latch tripping means disposed along the path of travel of the vehicle, and automatically operable means for returning said lever portion to its retracted position after tripping of said latch.

3, In lading hauling and dumping equipment, the combination of a lading carrying vehicle wherein is provided lading supporting and dump door equipment and means including a latch for releasably securing the dump door equipment in lading supporting position, a latch lever for moving the latch to a door equipment releasing position, said lever including a portion normally retracted within the lateral dimensional limits of the vehicle .and rocable beyond said limits for latch tripping engagement with a tripping means, automatically operable means for moving said lever` portion to its extended position, latch tripping means disposed along the path of travel of the vehicle, automatically operable means for returning said lever portion to its retracted position after tripping of said latch, and means engageable by said lever portion when it is in its retracted position for locking the lever against latch tripping movement.

4. In lading hauling and dumping equipment, the combination of a lading carrying vehicle wherein is provided lading supporting and dump door equipment and means including a latch for releasably securing the dump door equipment in lading supporting position, a latch lever for moving the latch to a door equipment releasing position, said lever including an extension ,piece swingably mounted thereon for movement between a retracted position within the lateral dimensional limits of the vehicle and an extended position wherein it is engageable during movement of the vehicle with a tripping means disposed along the path of travel of the vehicle, spring means for yieldably holding said extension piece in either of its retracted and extended positions, said extension piece having a lock shoulder thereon, a locking lug carried by the vehicle and engageable with said lock shoulder when the extension piece is retracted for locking the lever against latch tripping movement, automatically operable means for moving said extension piece to its extended position, latch tripping means disposed along the path of travel of the vehicle and engageable by said extended extension piece, and automatically operable means for moving said extension piece to its retracted position after tripping of said latch.

5. In a lading carrying vehicle wherein is provided lading supporting and dump door equipment and means including a latch for releasably securing the dump door equipment in lading supporting position, a latch lever for moving the latch to a door equipment releasing position, said lever including a portion normally retracted within the lateral dimensional limits of the vehicle and movable beyond said limits for latch tripping engagement with a tripping means disposed along the path of travel of the vehicle, and electrically operated means for moving said lever portion to its extended position.

6. In lading hauling and dumping equipment wherein is included a lading carrying vehicle having lading supporting and dump door equipment and means including a latch for releasably securing the dump door equipment in lading supporting position, and a latch lever for moving the latch to a door equipment releasing position; electrically actuated means for controlling the tripping of said latch lever and including a contact member movable with the vehicle and a contact member supported in the path of travel of the first mentioned contact member and having provision for insulating it from effective electrical contact in one direction of travel but not in the other thereby to bo effectivelyr engageable in one direction of travel only.

7. In lading hauling and dumping equipment, the combination of a lading carrying vehicle wherein is provided lading supporting and dump door equipment and means including a latch for releasably securing the dump door equipment in lading supporting position, a latch lever for moving the latch to a door equipment releasing position, said lever including an extension piece swingably mounted thereon for movement between a retracted position within the lateral dimensional limits of the vehicle and an extended position wherein it is engageable during movement of the vehicle with a tripping means disposed along the path of travel of the vehicle, spring means for yieldably holding said extension piece in either of its retracted and extended positions, means for moving said extension piece vto its extended position, latch tripping means disposed along the path of travel of the vehicle and engageable by said extended extension piece, and automatically operable means for moving said extension piece to its retracted position after tripping of said latch.

8. In lading hauling and dumping equipment, the combination of a lading carrying vehicle wherein is provided lading supporting and dump door equipment and means including a latch for releasably securing the dump door equipment in lading supporting position, a latch lever i'or moving the latch to a door equipment releasing position, said lever including an extension piece swingably mounted thereon for movement between a retracted position within the lateral diwhenever it is desired mensional limits of the vehicle and an extended position wherein it is engageable during movement of the vehicle with a tripping means disposed along the path of travel of the vehicle, spring means for yieldably holding said extension piece in either or" its retracted and extended positions, means for moving said extension piece to its extended position, latch tripping means disposed along the path of travel of the vehicle and engageable by said extended extension piece, and automatically operable means for moving said extension piece to its retracted position after tripping of said latch, said last named means comprising a cam rail hingedly mounted along the path of travel of the vehicle and movable into and out of eiective position, and spring means normally holding said rail in its effective position.

o 9. In a lading carrying vehicle including sides and ends and an open bottom through which lading can be dumped, a plurality of hingedly mounted doors for closing said bottom and having portions mutually engaging when the doors are closedfor holding all but one of said doors closed, `a latch engageable with said one door for releasably securing it and the remaining doors in closed position, a latch lever pivotally mounted on 'and transversely of 4an end of the vehicle and effective `when moved to displace the latch from its door securing position, and electrically actuated means for controlling the movement of said latch lever and including a control circuit, lever positioning means on the vehicle, contact means carried by the vehicle and electrically connected with said positioning means, and roadside contact means connected inksaid control circuit and engageable by said vehicle carried contact means. Y

10. In combination with a lading carrying vehicle which mayI or may not be connected in series with like vehicles, said vehicle including sides and ends and an open bottom through which lading can be dumped, a plurality of hingedly mounted doors for closing said bottom and having portions mutually engaging when the doors are closed for holding all but one of said doors closed, a latch engageable with said one door for releasably securing it and the remaining doors in closed position, a latch lever pivotally mounted on and transverselyof an Vend of the vehicleand effective when moved to displace the latch from its door securing position, andelectrically actuated means for controlling the movement of said latch leverI and including a contact member movable with the vehicle and `a contact member' supported in the path of travel ofthe first mentioned contact member, 'anda manually loperable switch which can be actuated for rendering said contact member temporarily ineffective for tripping the latch lever that said vehicle be not dumped. o Y f 11. In vlading hauling and dumping equipment, `the combination of a lading carrying vei releasing position, said lever including a gen,`

erally horizontally disposed portion, and an extension piece swingably attached to said generally horizontal lever. portion in position for being Swingable betweenA a normal retracted position in which no part thereof extends beyond the lateral dimensional limits of the vehicle and a fully projected position in which it extends beyond said limits for latch tripping engagement with a tripping means disposed along the path of travel of the vehicle, said extension piece and said generally horizontal lever portion having portions mutually engageable when the piece is fully extendedl to cause said lever portion and piec'e to move as a rigid entity when the piece is engaged by a'tripping means, latch tripping means disposed along the path of travel oi' the vehicle, and automatically operable means for returning said extension piece to its retracted position after tripping of said latch.`

l2. In a bottom dump lading carrying vehicle wherein is provided at least one lading supporting drop bottom door and means including a latch lug projected from the door and a latch releasably engageable with said lug for releasably securing the door in lading supporting position,4 a latch leversecured tothe latch for moving the latch to a door equipment releasingposition,said lever being constantly disposed wholly vwithin the. lateral dimensional limits of the vehicle and having an extension piece swingably mounted thereonior movement in the same general plane in which the :latch lever moves between ;va retracted position within the lateral dimensional limits of the vehicle 4and an extended position wherein -it is engageable during movement of the vehicle 'with' a tripping means disposed along the path of travel of the vehicle, spring means fior yieldably holding said extension piece in either of its retracted and extended positionssaid extension piece-having a lool; shoulder thereon, and` a locking lug carried oy the vehicle engageable with said lock shoulder when the extension pieceis retracted for locking the lever against latch trippingmovement.

1'3. In a bottom dump lading carrying vehicle wherein is provided at least one lading supporting drop'bottom door and means including a latch lug projected from the door and a latch releasably engageable with said lug for releasably securing the door in lading supporting position, a latch lever secured to the latch for moving .the latch to a door equipment releasing position, said lever being constantly disposed Wholly within the latleral dimensional limits of the vehicle and having an extension 4piece movably attached to said lever and movable inthe same general plane in which the latch lever moves between a normal retracted position'in which no part thereof extends `beyond the lateral dimensional limits of the vehicle -and a projected position in which it extends beyond said limits for latchtripping engagement with a tripping means disposed along the path of travel Yof the vehicle, and means for holding said extension piece against free movement relative to said rlever when extended and engaged by a tripping means andthereby causing said piece tofmove in rigid relation with said lever to impart latch tripping movement thereto.

14. A structure as deiined in claim l3in which there is included spring means effective to hold the extension against inadvertent `movement from itsretracted position to said projected position or-irom its projected position to said retracted position.

'15; In a bottom dump llading carrying vehicle wherein is provided at least one lading supporting drop bottom door and means including a latch lug projected from the door and a latch releasably engageable'with said lug for releasably securing the door in lading supporting position, alatch lever secured to the latch for moving the latch to a door equipment releasing position, said lever including a main body portion disposed in generally horizontal position transversely of the vehicle at one end thereof and of a length for extending approximately to but never beyond a lateral clearance limit of the vehicle, means mounting said lever to swing in a vertical plane about a horizontal axis disposed longitudinally of the vehicle, and an extension piece movably carried on said main body portion for movement upwardly and downwardly with said main body portion and also for movement relative to said main body portion from a iirst position retracted within said clearance limit of the vehicle to a second position in which it extends beyond Said clearance limit, and spring means for yieldably holding said extension piece in either of said retracted and extended positions.

16. In a bottom dump lading carrying vehicle wherein is provided at least one lading supporting drop bottom door and means including a latch lug projected from the door and a latch releasably engageable with said lug for releasably securing the door in lading supporting position, a latch lever secured to the latch for moving the latch to a door equipment releasing position, said lever including a main body portion disposed in generally horizontal position transversely of the vehicle at one end thereof and of a length for extending approximately to but never beyond a lateral clearance limit of the vehicle, means mounting said lever to swing in a vertical plane about a horizontal axis disposed longitudinally of the vehicle, and an extension piece swingably mounted on said main body portion for movement upwardly and downwardly with said main body portion and also fol` swinging movement relative to said main body portion and in the same general plane in which said main body portion moves from a first position retracted within said clearance limit of the vehicle to a second position in which it extends beyond said clearance limit, and stop means limiting swinging movement of the extension piece relative to said main body portion.

17. In a drop bottom mine car, a drop bottom door hingedly carried by the car, a latch assembly carried by the car and normally engaging the door to retain the same in closed position and movable to release the door for opening, said assembly including a. main latch lever movable in an upright plane and located wholly within the lateral clearance limits of the car, and a latch lever extension pivotally carried by the main latch lever, said extension being swingable in the same general plane in which the main latch lever is movable from a folded position within the lateral clearance limits of the car to an operative position in which it extends substantially in alignment with said main latch lever forming an extension thereof and projecting beyond the lateral clearance limits of the car, and mutually engage'- able stop means carried by the extension and said main latch lever for limiting swinging movement of said latch lever extension to its intended position of extension.

18. In a lading carrying vehicle wherein is provided lading supporting and dump door equipment and means including a latch for releasably securing the dump door equipment in lading supporting position, a latch lever having all parts thereof disposed within the lateral dimensional limits of the vehicle and adapted for moving the latch to a door equipment releasing position, said lever including a generally horizontally disposed portion, and an extension piece swingably attached to said generally horizontal lever portion in position for being swingable in an upright plane between a normal retracted position in which no part thereof extends beyond the lateral dimensional limits of the vehicle and a fully projected position in which it extendsbeyond said limits for latch tripping engagement with a tripping means disposed along the path of travel of the vehicle, said extension piece and said generally horizontal lever portion having portions mutually engageable when the piece is fully extended to cause said lever portion and piece to move as a rigid entity in a latch releasing direction when f the piece is engaged by a tripping means.

19. A structure as dened in claim 39 in which there is provided a rigid locking abutment, and in which the extension piece includes a locking shoulder engageable with said abutment in position for automatically preventing unlatching movement of the lever whenever said piece ls in or substantially in its fully retracted position.

20. A structure as defined in claim 18 in which there is included spring means effective to hold the extension piece against inadvertent movement from its retracted position to its projected position or from its projected position to its retracted position.

2.1. In a bottom dump lading carrying vehicle wherein is p rovided at least one lading supporting drop bottom door and means including a latch lug projectedffrom the door and a `latch releasably engageable with said lug for releasably securing the door in lading supporting position, a latch lever secured to the latch for moving the latch to a door equipment releasing position, said lever including a main body portion disposed in generally horizontal position transversely of the vehicle at one end thereof and of a length for extending approximately to but never beyond a lateral clearance limit of the vehicle, means mounting said lever to swing in a vertical plane about a horizontal axis disposed longitudinally of the vehicle, and an extension piece movably carried on said main body portion for movement upwardly and downwardly with said main body portion and also for movement relative to said main body portion from a first position retracted within said clearance limit of the vehicle to a second position in which it extends beyond said clearance limit, said extension piece having a lock shoulder thereon, and a locking lug fixed to the vehicle in position for being engaged by the extension piece when it is retracted Lfor locking the extension piece and the main lever body portion against upward movement effective to disengage the latch from the latch lug.

22. In a drop bottom mine car adapted to run on tracks, a drop bottom door hingedly carried by the car, a latch assembly'carried by the car and normally engaging the door to retain the same in closed position and movable to a position releasing the door for opening, said assembly including a main latch lever located wholly within the clearance limits of the car, and a latch lever extension movably carried by the main latch lever adjacent the outer end thereof, said latch lever extension being movable from a iirst position Within the clearance limits of the car to a second position in which it projects beyond the clearance limits of the car, and a. retractile spring anchored at-one end to the car and at its other end to said extension in position for being eiective to retain the extension in either of said rst or second positions.

23. In a lading carrying vehicle wherein is provided lading supporting and dump door equipment and means including a latch for releasably securing the dump door equipment in lading supporting position, a latch lever mounted in generally horizontal position transversely of the Vehicle at one end thereof and swingable about a generally horizontal pivot disposed longitudinally of the vehicle for moving the latch to a door releasing position, and electrically operated means for tripping said latch including a solenoid mounted on the end of the vehicle adjacent the latch lever and having a reciprocable core engaging said lever and movable each time the solenoid is energized to impart latch tripping movement to said lever.

24. In a lading carrying vehicle wherein is provided lading supporting and dump door equipelectrically operated means for tripping said latch including a solenoid mounted on the end of the vehicle adjacent the latch lever and having a reciprocable core engaging said lever and movable each time the solenoid is energized to impart latch tripping movement to said lever,

HUGH W. SANFORD. 

